Question

A student received a 75% on an exam. If there were 20 questions on the exam, which ratio would show the number of questions answered correctly to the total number of questions? A. 20:5 B. 5:20 C. 15:20 D. 20:15

Answer 1

For this case what you can do is the following rule of three:
 100% ---> 20
 75% -----> x
 Clearing the value of x we have:
 x = (75/100) * (20)
 x = 15
 This number represents the number of correct answers.
 We have then that the ratio is:
 15:20
 Answer: 
 A ratio that would show the number of questions answered correctly to the total number of questions is: 
 C. 15:20

Answer 2

C, 15:20.

The student missed 5 questions.

Hope this helped!